Colombia, Ecuador and Venezuela have avoided war, but now two other Andean nations are gearing up for battle. This time the foe is the United Nations, and the cause is the right to chew coca, the raw material of cocaine. It may not sound as important as the diplomatic row that shook the region earlier this month. But the dispute is momentous for millions of people in Bolivia and Peru  where the coca leaf is sacred to indigenous culture and a tonic of modern life  and for anti-drug officials in the U.S. and other countries who are desperate to stem the relentless flow of cocaine. Says Silvia Rivera, a sociology professor at San Andres University in Bolivia's capital, La Paz, "This is the most aggressive attack [Bolivians] have faced" since the U.N. designated coca a drug in 1961.

The latest affront, they say, is a recommendation this month from the UN's drug enforcement watchdog, the International Narcotics Control Board (INCB), that Bolivia and Peru criminalize the practice of chewing coca and drinking its tea. The move has provoked widespread anger and street protests in the two countries, especially among the majority indigenous populations. For them, coca has been a cultural cornerstone for 3,000 years, as much a part of daily life as coffee in the U.S. (La Paz is home to perhaps the world's only coca museum.) From the countryside to swanky urban hotels, it is chewed or brewed to stave off hunger or exhaustion or to ease the often debilitating effects of high-altitude life in the Andes. It is also "used by healers and in ceremonial offerings to the gods," says Ana Maria Chavez, a coca seller in La Paz, who refers to her product as "the sacred leaf." Pope John Paul II even drank coca tea on a 1988 visit to Bolivia. It is, says Chavez, "part of who we are."

The problem is, it's also considered the building block of broken lives in the rest of the world, where cocaine consumption and addiction remain rampant in developed regions like North America and Europe. The U.S. has spent more than $5 billion this decade aiding Colombia's largely failed efforts to eradicate coca cultivation. Meanwhile, Washington and the U.N. have tried to get Bolivia and Peru to reduce their coca crops to the bare minimum for traditional consumption. Peru and Bolivia are the region's second and third largest coca producers, behind Colombia, with about more than 75,000 hectares (185,000 acres) under cultivation, or almost half of global supply.

The 1961 U.N. convention called for coca's elimination by the late 1980s. A new accord struck in 1988 recognized the plant's traditional attributes and allowed for limited local use, while anti-narcotics forces continued to work to wipe out coca's drug-related cultivation, destroy the labs that process it into cocaine and intercept traffickers. But this month's INCB report seeks to end that uneasy arrangement. A big reason is that despite the decades-long, multi-billion-dollar drug war in Latin America, cocaine production has remained stable at best. Criminalizing even traditional coca use may be the only means agencies like the INCB feel they have left to salvage the anti-drug mission. Consuming the raw, unprocessed leaf, says the INCB report, abets "the progression of drug dependence."

Critics of the report call that conclusion an absurd stretch, especially since there is no published evidence that the coca leaf itself is toxic or addictive. Foremost among the detractors is left-wing Bolivian President Evo Morales, who remains head of one of the country's largest coca-growing unions and was elected as Bolivia's first indigenous head of state in 2005 in part because of his defense of the leaf. "This leaf," Morales said at last year's U.N. General Assembly, holding one up at the podium, "represents... the hope of our people." Bolivia accounts for about 17% of worldwide coca supply and Morales gets much of the international blame for coca's persistence. But while critics like the U.S may call him disingenuous for arguing that coca and cocaine are apples and oranges  analysts say that despite government efforts, much of the coca grown in Bolivia ends up in drug cartels' hands  he has also helped lead what experts like Rivera call "a revaluation of the coca leaf." "Many people," says the sociologist, "have begun to rediscover its nutritional and medicinal benefits."

Indeed, several international studies, including one published by Harvard University, say that raw coca is loaded with protein, calcium, iron and a range of vitamins. As a result, Morales has encouraged a local industry, with an eye to exporting, that is turning coca into everything from flour to toothpaste, shampoo and curative lotions. (Morales sent Fidel Castro a coca cake for his 80th birthday last year.) Even as the INCB was issuing its report, the Bolivian government was reaffirming its desire to increase Bolivia's legal coca crop limit from 12,000 hectares (30,000 acres) to 20,000 hectares (49,000 acres). The Bush Administration has warned that the latter move would put Bolivia in violation of its international agreements  it is "not consistent with Bolivia's obligations," said the State Department  and risk tens of millions of dollars in U.S. aid.

Seemingly undeterred, Bolivia said this month it was also set to invest another $300,000 for developing new, legal coca markets. Not surprisingly, the Bolivian delegation was the first to issue what it called an "energetic protest" against the INCB's recommendations during the agency's annual meeting this week in Vienna. It also put forward a proposal to remove coca from the U.N.'s narcotics list. That's not likely to happen. The big question is whether the U.N. will adopt the INCB proposal  which would essentially leave Bolivia and Peru in breach of international law if they continue to allow coca's non-narcotic use and commercialization. That in turn could result in the U.N. calling for commercial or other embargoes against them.

Many Bolivians say they don't care. "My grandfather and my grandmother sold coca and I've been doing it for 48 years," says Josefina Rojas, another La Paz coca seller. "We aren't going to let them take coca away from us no matter what." Such is the latest Andean conundrum. One that might be harder to solve than a potential war.